Tube shaping apparatus for radius-bending, end-flaring and the like

ABSTRACT

Apparatus for shaping metal tubes and the like includes a plurality of work-contacting assemblies arranged side by side with contacting portions of each assembly being aligned with one another and with each assembly being removably mounted at spaced working stations on a common support. A longitudinal drive advances one of the assemblies in a direction longitudinally of the tube to impart shaping forces to the tube. In one assembly arrangement suitable for providing a radius bend in a tube while minimizing crimping in the area of the bend without using a bending die, one of the assemblies releasably grips a leading section of the tube and swings about a pivot point located a preselected distance along a line normal to the longitudinal axis of the tube and another of the assemblies serves as a stationary guide and counter-support for the slidable movement of a section of the tube rearwardly of the swinging clamp while yet a third assembly grips a trailing end section of the tube and is driven by the longitudinal drive to positively force the tube through the stationary guide assembly and swing the gripped leading section of the tube about the pivot point. In another assembly arrangement for providing an end flare in a tube, a male flare die is advanced by the longitudinal drive into the end of a tube held by a split female flare die.

United States Patent Stange et al.

TUBE SHAPING APPARATUS FOR Assignee:

Filed:

Inventors: Ronald R. Stange, Denver; Gary B.

Ward, Aurora, both of Colo.

Tools for Bending, lnc., Denver,

Colo.

Dec. 27, 1971 Appl. No.: 212,146

[52] U.S. C1. 72/310; 72/127 [51] Int. C1 B2111 11/00 [58] Field Of Search 72/149, 154, 156, 159, 72/293, 298, 305, 307, 308, 310, 316, 387, I 388, 166, 128, 127

[56] References Cited M UNlTED STATES PATENTS 785,083 3/1905 Brinkman 72/128 1,105,914 8/1914 M1116! 72/128 1,268,844 6/1918 Holinger... 72/387 2,286,893 6/1942 Bolssou..... 72/305 3,156,287 11/1964 Munro 72/8 3,287,952 11/1966 Van Harten 72/157 3,335,588 8/1967 Cummings 72/388 3,336,776 8/1967 zellaut 72/14 3,339,392 9/1967 Buckwalter... 72/166 3,344,639 10/1967 Sassak 72/150 3,406,551 10/1968 Coody 72/388 3,465,560 9/1969 Gardner 72/388 3,564,892 2/1971 ostcl'land 72/219 3,724,258 4/1973 Hofstede 72/128 Apr. 22, 1975 Primary E.\'aminer-C. W. Lanham Assistant Examiner-M. J. Keenan [57] ABSTRACT Apparatus for shaping metal tubes and the like includes a plurality of work-contacting assemblies arranged side by side with contacting portions of each assembly being aligned with one another and with each assembly being removably mounted at spaced working stations on a common support. A longitudinal drive advances one of the assemblies in a direction longitudinally of the tube to impart shaping forces to the tube. In one assembly arrangement suitable for providing a radius bend in a tube while minimizing crimping in the area of the bend without using a bending die, one of the assemblies releasably grips a leading section of the tube and swings about a pivot point located a preselected distance along a line normal to the longitudinal axis of the tube and another of the assemblies serves as a stationary guide and countersupport for the slidable movement of a section of the tube rearwardly of the swinging clamp while yet a third assembly grips a trailing end section of the tube and is driven by the longitudinal drive to positively force the tube through the stationary guide assembly and swing the gripped leading section of the tube about the pivot point, In another assembly arrangement for providing an end flare in a tube, a male flare die is advanced by the longitudinal drive into the end of a tube held by a split female flare die.

12 Claims, 10 Drawing Figures PATENIEDAPRnms SHEEI 1 Bf 3 NVENTORS RONALD R. STANGE Y B. WARD ATTORNEYS TUBE SHAPING APPARATUS FOR RADIUS-BENDING, END-FLARING AND THE LIKE This invention relates generally to apparatus for shaping elongated material such as tubes or rods and more particularly to novel and improved shaping apparatus-particularly suitable for large radius bending, end flaring and like shaping procedures.

Apparatus heretofore employed for providing a radius bend in tubes or rods usually has been of the draw type utilizing a rotary disc having a center die or roll and a bending roll displaced radially from the center roll operatively asssociated with a stationary countersupport which holds a trailing section of the tube whereby upon the rotation of the disc the bending roll moves orbitally around the center roll to cause the tube placed between the center and bending rolls to bend around the center roll. There is a limit to the size of the rqdius which can be made by this type of apparatus and limits upon the flexibility to accommodate a wide range of tube sizes and wall thicknesses. For a large radius bend, apparatus has heretofore relied generally on drawing techniques and bending dies have been required to avoid crimping, distortion or collapse in the area of the bend. Shaping apparatus heretofore employed has also been limited in flexibility for performing more than one shaping operation utilizing the same drive mechanism. In US. Pat. No. 1,268,844 a large radius bend is provided in a tube by holding the tube stationary and engaging the free end of the tube with a free-swinging pivotal arm which is advanced relative to the tube together with a movable roller which engages the tube in the area of the bend while an internal bending die is provided in the area of the bend. Shaping apparatus heretofore employed has also been limited in flexibility for performing more than one shaping operation utilizing the same drive mechanisms.

Accordingly, it is an object of this invention to provide novel and improved shaping apparatus for tubes and the like which is particularly suited for radiusbending and particularly large radius-bending for a variety of sizes of metal tubes with minimum stressing in the area of the bend and which is also suitable for other shaping functions including the end flaring of the tube and the like.

Another object of this invention is to provide novel shaping apparatus for tubes which does not require a bending die and minimizes the tendency of the tube to collapse along the outer side in the area of the bend during a radius bend.

Yet another object of the present invention is to provide a novel and improved shaping apparatus having easily replaceable work-contacting die assemblies to accommodate tubes of different sizes and perform more than one shaping function according to the selection of work-contacting assemblies and an adjustable support frame to vary the size of the bend in a particular tube.

Still a further object of this invention is to provide a novel and improved tube shaping apparatus for radiusbending, end-flaring and like shaping operations characterized by a plurality of demountable workcontacting die assemblies arranged side by side and having opposed contact portions of each pair in alignment with one another to receive a tube with one workcontacting die assembly being movable and positively driven toward and away from the other of the die assemblies along the axis of the tube to effect a change of shape therein.

In accordance with the present invention in a preferred form there is provided a plurality of working stations arranged side by side on a common support, each station having a base plate, a separate cross-drive on each base plate and a demountable work-contacting die assembly mounted on each base plate. A longitudinal drive moves one of the work-contacting head assemblies toward and away from the others along the longitudinal axis of the tube. For a radius bend a pair of opposed clamping dies grip a trailing section of the tube, another pair of stationary dies countersupport the tube for movement in line with the drive, and the third pair of clamping dies beyond the guide dies grip a leading section of the tube and swings on a pivot arm having its pivot point located a preselected distance along a line normal to the direction of movement of the tube for a selected radius bend. For forming a flare in the end of a tube, a male flare die is carried on the driven base plate and a female flare die is releasably carried on the stationary base plate.

Other objects, advantages and capabilities of the present invention will become more apparent as the description proceeds taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a top plan view of tube shaping apparatus embodying features of the present invention arranged for radius-bending a metal tube with portions broken away to show interior construction;

FIG. 2 is a sectional view taken along lines 22 of FIG. 1 showing the connection of the longitudinal drive cylinder to the base plate;

FIG. 3 is an elevational view of the apparatus of FIG. 1 looking toward the outwardly projecting ends of the hydraulic cross-drives;

FIG. 4 is an elevational view of the apparatus of FIG. 1 looking toward the swinging pivot arm end of the apparatus;

FIG. 5 is yet another elevational view of the apparatus of FIG. 1 looking toward the longitudinal drive end of the apparatus;

FIG. 6 is a fragmentary top perspective view of one end of the tube clamping dies showing the manner of mounting on the associated base plate;

FIG. 7 is a bottom perspective view of the clamping die shown in FIG. 6;

FIG. .8 is a fragmentary side elevational view with the male and female end flare dies arranged on adjacent base plates;

FIG. 9 is a top plan view of the assembly shown in FIG. 8; and FIG. 10 is a sectional view showing the tube in the female end flaring die. Referring now to the drawings, in FIGS. 1-7 there is shown shaping apparatus set up for producing a radius bend in a tube 10 which broadly comprises adjustable support structure 11 on which there are provided three spaced working stations generally designated A, B and C. Workcontacting die assemblies are provided at each station and the size and shape thereof vary according to the tube size and the particular shaping operation being conducted. For the large radius bend illustrated in FIGS. 1-7, there is shown a pair of opposed clamping dies 13 and 14 at station A, a pair of opposed guide dies 15 and 16 at station E and a pair of opposed clamping dies 17 and 18 at station C, the details pertaining thereto being described more fully hereinafter. In the tube vending art a large radius bend in a tube is considered to be on a radius 5 times the external diameter of the tube and above.

The support base or structure is generally designated by numeral 11 and includes a pair of spaced parallel longitudinal frame members 21 and 22 mounted on spaced foot blocks 23, secured by bolt and nut fasteners 24, and a pair of spaced parallel cross frame members 25 and 26 disposed on longitudinal frame members and connected thereto by flat keys 27 and 28, respectively, secured in grooves in the lower surfaces of cross frame members 25 and 26, respectively, to form an open rectangular support framework. A longitudinally extending stationary plate or platform 29 is mounted on the cross frame members 25 and 26 and is adjustably mounted and maintained in alignment thereon at each end by the use of inverted T-shaped connecting keys 31 and 32 which fit in opposed grooves in the bottom of the stationary plate 29 and in grooves 25a and 25b in the top surfaces of the cross frame members 25 and 26, respectively, and extending in a direction longitudinally of the associated cross frame member. This key and groove arrangement permits the lateral adjustment of the die assemblies to effect a small increment change in the size of the radius bend. Spaced bolt and nut fasteners 30 are provided at each end of plate 29 and extend down through plate 29 and through cross frame members 25 and 26 to fixedly secure it at the desired position thereon. The nut fasteners 30 on the rigid end of the plate 29 as viewed in FIG. '1 also extend down through base plate 34 to fixedly secure it in place but they do not appear in FIG. 1 as they are covered by the die assemblies and cylinder rod. The heads of fasteners 30 are countersunk in plate 29 at the left side and in base plate 34 on the right side.

The three separate pairs of dies 13-18, inclusive, are detachably mounted on three separate base plates of a similar construction, are arranged side by side, parallel to one another and are disposed at the same level above the open framework 11. A pair of clamping dies 13 and 14 are mounted on a movable base plate 33, a pair of guide dies and 16 on stationary base plate 34 and pair of clamping dies 17 and 18 on a swinging or pivotal base plate 35.

Referring first to station A, driven base plate 33 is movably mounted above stationary platform or plate 29 and extends in a direction transverse or normal thereto. Movable plate 33 has a pair of spaced parallel guide grooves 36 and 37 and a groove 38 transverse to grooves 36 and 37. In turn clamping die 14 had a pair of spaced parallel square keys 39 and 40 located in bottom grooves and projecting from the bottom surface thereof sized and shaped to slidable insert into the base plate grooves 36 and 37, respectively, for the positioning of the clamping die 14 in the proper alignment relative to the opposed clamping die 13 with which it is associated, and a transverse locking key 41 sized and shaped to insert into transverse slot 38 between the keys to hold against its movement longitudinally of the base plate 33. The parallel guide grooves and associated keys also provide a fine increment of adjustment of size for the radius bend. The transverse grooves and keys limit their adjustment but if removed a greater range of adjustment would be afforded. The stationary clamping die 14 is releasably fastened to the base'plate 33 by a bolt 42 shown as being an Allen-type head, the bolt 42 extending through a vertical .hole 43 and threading into threads in. the base plate 33. Clamping die 14 illustrated in more detail in FIGS. 6 and 7 is in the form of an oblong block with a semicircular recess 14a in the inner face thereof to accommodate the transverse cross section of the cylindrical tube 10. The clamping die 13 is generally similar in construction to block die 14 also having a semicircular recess, and it is releasably mounted and held in place on the base plate 33 by a holder 45 slidably mounted to move along the top of the base plate. Holder 45 is provided with a male outwardly projecting key portion 46 along the back side which fits in a corresponding female C-shaped socket portion in holder 45 to facilitate the proper positioning of the movable clamping die 13 thereon. The clamping die 13 may be further releasably held in the proper position and alignment by a key pin 49 which extends through the holder and down into the key portion 46. Clamping dies 13 and 14 comprise a gripping means adapted to grip a section of the tube.

The cross-drive for the advancement and retraction of the clamping die 13 is a reversible hydraulic cylinder or ram 47 mounted on a part of the base plate 33 which projects beyond frame member 21. The hydraulic cylinder moves die 13 toward and away from the opposed die 14 in a direction normal to that of the tube for side positioning relative to the tubes, and clamping and releasing of the tube. The outer end of the movable rod portion 48 of the ram is connected to the back of the holder 45 to impart straight-line movement thereto along the top surface of the base plate 35. In FIG. 1 the rams are shown in the extended clamping position. The hydraulic ram 47 has fluid lines F1 and F2 at opposite ends to positively drive the rod portion 48 and holder 45 in either direction. Suitable conventional hydraulic controls are used to selectively actuate the cylinder or ram 47.

The coupling between the movable rod or ram portion of drive 51 and the base plate is provided by spaced clevis arms 53, a pin 54 with threads on both ends which extends through the clevis arms 53 and the lower end portion of a vertically disposed slidable connecting rod 55. The connecting rod 55 has an enlarged dovetailed head portion 55a with upwardly convergent sides which slide along a longitudinal groove 29a complementary in shape with that of the vertical cross section of the connecting rod. The groove 29a includes an outwardly stepped portion and an upwardly divergent portion to accomodate the enlarged dovetailed head portion and provide for its slidable guided movement therealong in a straight line movement. The longitudinal groove has a widened portion 29 at the return end therof to allow the connecting rod to be inserted into the groove and particularly the head portion 55a into the outwardly stepped upwardly divergent portion of the groove and slide therealong. The upper end of the connecting rod 55 is fixedly secured to the movable base plate by a key 56 and a pair of spaced bolts 57 countersunk in plate 33 which thread down through the base plate 33 and into rod 55.

Base plate 34 is fixedly secured to the top of platform 29 at the desired position by bolts 30 above described. The stationary base plate 34 is similar in construction and arrangement to that of base plate 33 having a pair of parallel grooves and a transverse groove to receive complementary key portions projecting down from the bottom of the guide die 16. A bolt fastener 64 fastens die 16 in place on base plate 34. A holder 65 for die 15 is driven by the rod portion of a hydraulic ram 66 to move die 15 toward and away from opposed die 16. A key pin 69 secures the die 15 to holder 65.

Clamping dies 17 and 18 are carried on base plate 35 which in turn is mounted on a swinging pivot arm 71 pivotally connected to cross frame member 26 by a bolt and nut assembly 72 disposed in one of a plurality of selected apertures 73 in cross frame member 26. Bolt 72 thereby establishes a pivot point for the pivot arm.

It is noted that arm 71 is located at the same level as platform 29 and one side abuts along the outer side thereof in the starting position. The pivotal base plate 35 is aligned and adjustably movable on pivot arm 71 by providing a longitudinal groove 71a in the top face thereof which receives an inverted T-shaped key 74. Spaced bolt fasteners 60 extend through the base plate 35 and into the pivot arm to fixedly secure the base plate 35 on the pivot arm 71. In this way the base plate 35 may be moved to adjust for radius changes like base plates 33 and 34 on the plate 29 as above described. may be The heads of fasteners 60 are countersunk in plate 35. Base plate 35 has spaced parallel grooves and a transverse groove like that of base plates 33 and 34 to receive the key portions in the associated clamping die 18 in a manner similar to the base plates 33 and 34 and dies 14 and 16 above described. A bolt fastener 75 secures the clamping die 18 to the base plate 35. The opposed die 17 is carried by a holder 77 moved by hydraulic ram 78 mounted on base plate 35. A key pin 79 releasably secures the clamping die in place in holder 77. Dies 17 and 18 function as gripping means at the free end of the pivot arm 71.

For the full sequence of operation for a large radius bend in a tube, the sizes of the dies are selected according to the size of the tube to be bent. Dies 14, 16 and 18 are secured in place by tightening down the associated fastening bolts 42, 64 and 75, respectively. The large increment for the radius of the bend such as the foot increment is established by selecting one of the apertures 73 and inserting bolt 72 down through arm 71 and through cross frame 26. The cross-driven dies, 13, 15 and 17 are inserted into the associated holders and, once in place, are keyed against slippage relative to the holder. The cross-driven dies are normally in an open position leaving a substantial space between the opposed pairs of dies to permit the placement of the tube between the opposed dies, after which the crossdriven dies are advanced by selectively or simultaneously actuating the associated hydraulic cylinders or cross'drives to embrace sections of the tube 10 along its length. Smaller increments of adjustment are afforded by sliding the stationary plate 29 relative to the frame and base plate 35 relative to the pivot arm 71 or by moving dies 14, 16 and 18 relative to their associated base plates and then tightening the associated bolt fasteners so that the use of grooves and keys with bolttype fasteners facilitates a fine increment of adjustment in the size of the radius bend.

The movable base plate 33 which moves in a direction along the axis of the tube is normally positioned at the left or return side of this stationary platform 29 as shown in FIG. 1. Clamping dies 13 and 14 grip a trailing section of the tube, guide dies 15 and 16 are oversize relative to the external dimensions of the tube and for each set-up are stationary so that they serve as a guide and countersupport for the tube in line with the movement of the longitudinal drive, and clamping dies 17 and 18 grip a leading section of the tube. The drive cylinder 51 is actuated by applying fluid pressure to one fluid line to apply a force longitudinally of the tube via dies 13 and 14 and force the tube through guide dies 15 and 16. The pivot arm 71 and the clamping dies 17 and 18 swing or pivot about a pivot point established by bolt 72 located a preselected distance along a line normal to the direction of movement of the tube and the direction of movement of the longitudinal drive 51 and advance the tube through the stationary guide dies 15 and 16 thereby causing the tube to bend along a preselected uniform radius. It is understood that the longitudinal axis or line of the pivot arm relative to the direction of movement of the tube may depart from a normal relationship shown for some bends but for a true radius bend this relationship is necessary. A second position for the pivotal arm 17 and the tube 10 is shown in dashed lines at 35.

At the end of the forward stroke of the drive the movable base plate 33 may be returned by first backing the clamping die 13 away from the tube by means of reversing the fluid flow in cylinder 47 and then reversing the flow in the cylinder 51 to return the base plate 33 to the starting position. The tube 10 is then clamped by dies 13 and 14 and the procedure is repeated so that the tube 10 could be bent to the extent of a full circle if desired.

The above described apparatus has been found to be highly effective in producing a large radius bend in relatively thick-walled tubes while minimizing collapse, distortion or crimping in the tube in the area of the bend and particularly along the outer side. This is accomplished in a highly effective manner without the necessity of a bending die or mandrel. The forcing or pushing of the tube through the stationary die has been found to further minimize any tendency to distort or collapse in the area of the bend.

While it is preferred to grip the trailing end of the tube and push the tube through the stationary guide dies to swing the pivot arm 71 as above described, it is appreciated that the bending forces for a radius bend and particularly a large radius bend may be accomplished by merely driving the pivot arm about the pivot point established by bolt 72 with the tube being drawn through the guide dies 15 and 16. In this arrangement the drive means for the pivot arm is not applied to a trailing section of the tube to push the tube so there is a greater tendency for the tube to collapse in the area of the bend.

A further advantage of utilizing stationary guide dies 15 and 16 is that additional energy may be imparted to the tube in the area of the bend to minimize tube distortion or possible collapse. Of particular significance is the fact that ultrasonic energy may readily be applied directly to the stationary guide dies 15 and 16 and in this event raduis bends may be accomplished below 5 times the diameter standard for large radius bends without collapse in the area of the bend. Further, in the event ultrasonic energy is applied to the tube in the area of the bend via the guide dies 15 and 16, the above described variation of having the pivot arm positively driven to draw the tube through the guide dies 15 and 16 without collapse becomes more feasible.

Referring now to FIGS. 8-10, for the flaring operation a male flaring or swaging die 81 is fastened to the base plate 33 in place of die 14 above described by bolts 82 which extend up through the bottom and bore 87 with an enlarged outwardly divergent bore portion 88 sized to receive the flaring tip 83. In operation, a tube represented at 89 is inserted into the bore between the female die sections and the end is flared at 89a by advancing the male tip 83 into the end of the tube 89 and against the female tapered end portion 88.

Although the present invention has been described with a certain degree of particularity, it is understood that the present disclosure has been made by way of example and that changes in details of structure may be made without departing from the spirit thereof.

What is claimed is:

1. In shaping apparatus for tubes and the like, the combination comprising:

a pivotal arm having gripping means at its free end adapted to grip a leading section of a tube for swinging movement about a pivot joint located a preselected distance away from the longitudinal axis of the tube,

stationary guide means adjacent the free end of the pivotal arm operative to substantially embrace and slidably support a section of the tube behind the leading section for guide longitudinal movement and free passage of the tube relative to the guide means during said swinging movement of the pivot arm in a direction transverse to the longitudinal axis of the tube, and

drive means disposed rearwardly of said guide means for advancing said tube relative to the guide means and imparting rotation to said pivotal arm about its pivot point whereby to effect a bend in said tube.

2. In shaping apparatus as set forth in claim 1 wherein said drive means includes second gripping means in alignment with said guide means adapted to grip a section of the tube trailing said guide means, said second gripping means applying forces longitudinally of the tube in a direction toward the pivotal arm to force the tube through the guide means thereby causing said pivot arm to pivot about said pivot point.

3. In shaping apparatus as set forth in claim 2 wherein each said first and second gripping means and said guide means are defined by a pair of opposed dies releasably mounted on separate base plates.

4. In shaping apparatus as set forth in claim 3 wherein each said base plate has guide grooves in the top surface and one of each pair of dies has depending key portions to align and position the one die with respect to the other die at a preselected position on the associated base plate.

5. In shaping apparatus as set forth in claim 4 including means to releasably fasten one of each of the pairs of dies to the associated base plates.

6. In shaping apparatus as set forth in claim 4 including a cross-drive mounted on said base plate arranged to move the other of said pair of dies toward and away from said one die.

7. In shaping apparatus as set forth in claim 1 including adjustable means for varying the effective length of said pivotal arm at one of a plurality of selected distances away from the longitudinal axis to establish a range of sizes of radius bends.

8. In shaping apparatus as set forth in claim 1 wherein said stationary guide means includes a pair of opposed guide dies with face portions sized and shaped to conform to the transverse cross section of the tube to pass the tube in a guided movement, said guide dies being releasably mounted on a common base plate.

9. In shaping apparatus as set forth in claim 1 wherein said pivotal arm carries a pair of opposed clamping dies at its free end for gripping the tube, said opposed clamping dies being releasably mounted on a common base plate.

10. In shaping apparatus for providing for a radius bend in a tube and the like, the combination comprisa support having a plurality of base plates arranged side by side and extending parallel to one another, a first of said base plates being movable toward and away from the others, a second of said base plates being stationary and a third of said base plates being mounted for swinging movement about a pivot point located a preselected distance along a line normal to the longitudinal axis of the tube, pair of opposed dies releasably mounted on each base plate, each pair having opposed tube-engaging recess portions arranged in alignment with one another to selectively engage sections of the tube, one of each said pair of dies being held stationary and the other being movable toward and away from the associated opposed die, the dies on said first base plate adapted to clamp a trailing section of the tube, the dies on said second base plate allowing the tube to slide therethrough in a guided movement, the dies on said third base plate clamping a leading section of the tube,

a reversible cross-drive adapted to selectively move each movable die toward and away from the associated opposed stationary die, and

longitudinal drive means adapted to move said first base plate and the associated pair of clamping dies toward and away from said second and third base plates to advance said tube through said second dies and to pivot said third clamping dies whereby to effect a radius bend in the tube.

11. In shaping apparatus as set forth in claim 10 wherein each of said base plates is adjustably movable in alignment toward and away from said pivot point to vary the length of the radius of said bend.

12. In shaping apparatus as set forth in claim 11 wherein said adjustably movable supported for the base plates includes a pair of parallel spaced cross members each having an elongated top groove extending longitudinally thereof and a platform extending across the top of said cross members, key portions in said grooves cooperating with associated base plates for the slidable aligned movement of the base plates relative to said platform, means fastening said platform to said cross members at a selected position, first and second of said base plates being mounted on said platform, a pivotal arm having an elongated third top groove parallel to said top grooves in said cross frame members, a third key portion in said third groove connected to said third base plate for the slidable aligned movement of said third base plate with said platform, and means for fastening said third base plate to said pivot arm.-

UNITED STATES PA'iENT OFFICE I: CER'HFICATE @F (IQRRECTION Patent No 3,878 72O Dated Ayril 22, 1975 Invggnt0f s Ronald R. Sta-Inge and Gary B. Ward It is certified that error appears in the above-identified patent Q and that said Letters Patent are hereby corrected as shown below:

IN THE SPECIFICATION:

Column 1, line 0 C lum l, line Column 3 line Column 2, line Column 5, line IN THE CLAIMS:

Columnl, line Column 8, line -slidably 21, cancel "maybe" 31, cancel "guide" and substitute -guided- 51, cancel "supported" and substitute -supportf w'gn ed an fifth ay M August1975 A nest:

C. MARSMALL DANN ('nmmissimzvr uj'iatvnls and Trademarks 

1. In shaping apparatus for tubes and the like, the combination comprising: a pivotal arm having gripping means at its free end adapted to grip a leading section of a tube for swinging movement about a pivot joint located a preselected distance away from the longitudinal axis of the tube, stationary guide means adjacent the free end of the pivotal arm operative to substantially embrace and slidably support a section of the tube behind the leading section for guide longitudinal movement and free passage of the tube relative to the guide means during said swinging movement of the pivot arm in a direction transverse to the longitudinal axis of the tube, and drive means disposed rearwardly of said guide means for advancing said tube relative to the guide means and imparting rotation to said pivotal arm about its pivot point whereby to effect a bend in said tube.
 1. In shaping apparatus for tubes and the like, the combination comprising: a pivotal arm having gripping means at its free end adapted to grip a leading section of a tube for swinging movement about a pivot joint located a preselected distance away from the longitudinal axis of the tube, stationary guide means adjacent the free end of the pivotal arm operative to substantially embrace and slidably support a section of the tube behind the leading section for guide longitudinal movement and free passage of the tube relative to the guide means during said swinging movement of the pivot arm in a direction transverse to the longitudinal axis of the tube, and drive means disposed rearwardly of said guide means for advancing said tube relative to the guide means and imparting rotation to said pivotal arm about its pivot point whereby to effect a bend in said tube.
 2. In shaping apparatus as set forth in claim 1 wherein said drive means includes second gripping means in alignment with said guide means adapted to grip a section of the tube trailing said guide means, said second gripping means applying forces longitudinally of the tube in a direction toward the pivotal arm to force the tube through the guide means thereby causing said pivot arm to pivot about said pivot point.
 3. In shaping apparatus as set forth in claim 2 wherein each said first and second gripping means and said guide means are defined by a pair of opposed dies releasably mounted on separate base plates.
 4. In shaping apparatus as set forth in claim 3 wherein each said base plate has guide grooves in the top surface and one of each pair of dies has depending key portions to align and position the one die with respect to the other die at a preselected position on the associated base plate.
 5. In shaping apparatus as set forth in claim 4 including means to releasably fasten one of each of the pairs of dies to the associated base plates.
 6. In shaping apparatus as set forth in claim 4 including a cross-drive mounted on said base plate arranged to move the other of said pair of dies toward and away from said one die.
 7. In shaping apparatus as set forth in claim 1 including adjustable means for varying the effective length of said pivotal arm at one of a plurality of selected distances away from the longitudinal axis to establish a range of sizes of radius bends.
 8. In shaping apparatus as set forth in claim 1 wherein said stationary guide means includes a pair of opposed guide dies with face portions sized and shaped to conform to the transverse cross section of the tube to pass the tube in a guided movement, said guide dies being releasably mounted on a common base plate.
 9. In shaping apparatus as set forth in claim 1 wherein said pivotal arm carries a pair of opposed clamping dies at its free end for gripping the tube, said opposed clamping dies being releasably mounted on a common base plate.
 10. In shaping apparatus for providing for a radius bend in a tube and the like, the combination comprising: a support having a plurality of base plates arranged side by side and extending parallel to one another, a first of said base plates being movable toward and away from the others, a second of said base plates being stationary and a third of said base plates being mounted for swinging movement about a pivot point located a preselected distance along a line normal to the longitudinal axis of the tube, a pair of opposed dies releasably mounted on each base plate, each pair having opposed tube-engaging recess portions arranged in alignment with one another to selectively engage sections of the tube, one of each said pair of dies being held stationary and the other being movable toward And away from the associated opposed die, the dies on said first base plate adapted to clamp a trailing section of the tube, the dies on said second base plate allowing the tube to slide therethrough in a guided movement, the dies on said third base plate clamping a leading section of the tube, a reversible cross-drive adapted to selectively move each movable die toward and away from the associated opposed stationary die, and longitudinal drive means adapted to move said first base plate and the associated pair of clamping dies toward and away from said second and third base plates to advance said tube through said second dies and to pivot said third clamping dies whereby to effect a radius bend in the tube.
 11. In shaping apparatus as set forth in claim 10 wherein each of said base plates is adjustably movable in alignment toward and away from said pivot point to vary the length of the radius of said bend. 